In recent years, imaging apparatus (cameras) having the function of correcting camera-shake have gained popularity so that hand-held cameras can be used to take shake-free good images without recourse to tripods or the like yet without taking special heed.
However, the performance of correcting camera-shake is still less than satisfactory, and especially at the time of long-exposure photography, camera-shake often remains under-corrected: the camera-shake correction performance of the imaging apparatus has still some adverse influence on the quality of the images taken. Especially upon long-exposure photography in the so-called macro area, camera-shake correction performance available up to date often remains unsatisfactory.
Camera-shake may be broken down into two types: the so-called angular shake that occurs with changes in the angle of the optical axis of the imaging apparatus and the so-called parallel shifting parallel shifting shake that occurs with movement of the camera body in the direction vertical to the optical axis. Most camera-shake correction functions available up to date are limited to the correction of angular shake alone, and parallel shifting shake remains uncorrected. Although this parallel shifting shake is little noticeable especially in the case of low image magnifications, yet it has mounting influences on the quality of the images taken as the image magnification grows high. This is the reason why camera-shake correction functions available up to date remain unsatisfactory in the macro area.
Patent Publication 1 discloses an image shake correction camera comprising an acceleration sensor for detecting a triaxial acceleration acting on a camera, an angular velocity sensor for detecting a angular velocity around three axes acting on the camera, an attitude sensor means for calculating from a triaxial acceleration and an angular velocity around three axes a coordinate transform matrix between a camera coordinate system and a stationary coordinate system and a gravity acceleration component calculation means for calculating a gravity acceleration component in the camera coordinate system from the coordinate matrix, wherein the gravity acceleration component is subtracted from an output of the acceleration sensor to figure out a position of parallel shifting motion, and further comprising a correction drive amount calculation means for working out an amount of image shake based on them.